1. Field of the Invention
The present invention relates to a motor assembly used in an outer mirror driving apparatus to turn an outer mirror for a vehicle between a position in which the outer mirror is in a position to be used and a position in which the outer mirror is in a position not to be used.
2. Description of the Related Art
An outer mirror driving apparatus to drive an outer mirror between a position in which the outer mirror is in a position to be used and a position in which the outer mirror is in a position not to be used has been known.
A disk-shaped mirror joining portion configured to be turned within a predetermined angle range is provided on a top portion of the outer mirror driving apparatus.
A disk-shaped base portion is joined on a lower portion of the outer mirror of a vehicle and the base portion is fixed to the mirror joining portion with bolts.
The outer mirror driving apparatus is configured to turn the mirror joining portion so that the outer mirror is turned between a position in which the outer mirror is in a position to be used and a position in which the outer mirror is in a position not to be used.
The outer mirror driving apparatus has a mirror turning shaft, a power transmission mechanism, and a motor assembly.
The mirror joining portion is joined together on an upper end portion of the mirror turning shaft, and the power transmission mechanism having gears, or the like is configured to transmit power from the motor assembly to the mirror turning shaft.
The motor assembly has a motor as a power source, a circuit board on which a control circuit to control the motor is mounted, and a supporting member to fix the motor, the circuit board, and the like.
Harnesses to feed power to the motor are connected to the circuit board, and extend outwardly to an outside of the outer mirror driving apparatus.
A pair of threaded holes are provided on a chassis wall of the motor, in which a driving shaft is projected, so that the motor can be threadably fixed with the pair of screws.
Electrodes of the motor and the circuit board are connected to each other with a pair of lead wires fixed by soldering.
A motor fixing portion and a board supporting portion are formed together on the supporting member, and a driving shaft hole in which the driving shaft of the motor is inserted is provided. A pair of threaded holes are provided on both sides of the driving shaft hole.
A pair of notched portions are provided on the board supporting portion at an interval corresponding to a width of the circuit board and are configured to be engaged with both corners of one end of the circuit board so that the circuit board is supported.
Screws are inserted in the pair of threaded holes provided on the motor fixing portion in a state where the driving shaft of the motor is inserted in the driving shaft hole, and screwed in threaded holes of the motor to fix the motor.
The pair of corners of the circuit board are engaged with the pair of notched portions. The circuit board is fixed on the board supporting portion in a state where the circuit board is disposed at an interval in relation to the motor.
A gear or the like is fixed to the motor and the assembled motor assembly is installed in the outer mirror driving apparatus.
At this time, the circuit board is engaged to be fixed with board locking portions provided in an inside of a case of the outer mirror driving apparatus.
Similarly to the above outer mirror driving apparatus, an electric-powered storing door mirror has been known (see, for example, Japanese Application Publication Number 2004-237817)
However, in conventional motor assemblies, the motor and the circuit board are required to be preliminarily connected to each other with lead wires, and screws are needed to fix the motor. Consequently a connecting process to connect the motor to the circuit board, a fixing process to fix the motor with screws, and the like are required so that production efficiency is decreased due to an increased number of assembling processes.
Moreover, since the lead wires are connected by soldering and the screws are used to fix the motor, there is a problem in that the production cost is increased due to the need for an increasing number of connecting parts.
Furthermore, since only one end of the circuit board is engaged to allow the circuit board to be supported on the supporting member and the circuit board is connected to the motor with the lead wires, the circuit board is fixed to the motor in an unstable state.
Accordingly, if the lead wires are moved when the motor assembly is installed in the case of the outer mirror driving apparatus, the circuit board is also moved so that there is a risk that the circuit board is detached from the board locking portions, the notched portions, or the like.
In addition, if the motor assembly is installed in the outer mirror driving apparatus in a state where the circuit board is detached, there is a risk of the occurrence of a short-circuiting of the control circuit due to interference of the circuit board and the case of the outer mirror driving apparatus, or the like when the outer mirror driving apparatus is used.